1. Field of the Invention
The present invention relates generally to current meters and, more particularly, to a precision current meter particularly useful for spectrochemical computations in spectrometers.
2. The Prior Art
Current meters have been widely used and over a long period of time. There are many kinds and types of current meters, ranging from a simple ammeter to a rather complex one. The more complex the ammeter, the more versatile it gets. There are always some tradeoffs among desirable performance characteristics. Usually, current meters are designed for measuring either very low level signals or very high level signals but not both with acceptable performance at both ends of the signal levels. There is thus plenty of room for improvements. This is particularly so when the current meter is designed or required for specialized applications, such as for effecting spectrochemical computations in spectrometers. For, such applications usually require a system which is both extremely sensitive to low current signals and also possesses a wide dynamic range, preferably of seven or eight orders of magnitude.